I must exchange you must exchange he must exchange we must exchange you must exchange they must exchange
V-ing form
I must be exchanging you must be exchanging he must be exchanging we must be exchanging you must be exchanging they must be exchanging
Perfect
I must have exchanged you must have exchanged he must have exchanged we must have exchanged you must have exchanged they must have exchanged
V-ing perfect
I must have been exchanging you must have been exchanging he must have been exchanging we must have been exchanging you must have been exchanging they must have been exchanging
Negation
Simple form
I must not exchange you must not exchange he must not exchange we must not exchange you must not exchange they must not exchange
V-ing form
I must not be exchanging you must not be exchanging he must not be exchanging we must not be exchanging you must not be exchanging they must not be exchanging
Perfect
I must not have exchanged you must not have exchanged he must not have exchanged we must not have exchanged you must not have exchanged they must not have exchanged
V-ing perfect
I must not have been exchanging you must not have been exchanging he must not have been exchanging we must not have been exchanging you must not have been exchanging they must not have been exchanging
Interrogative form
Simple form
must I exchange? must you exchange? must he exchange? must we exchange? must you exchange? must they exchange?
V-ing form
must I be exchanging? must you be exchanging? must he be exchanging? must we be exchanging? must you be exchanging? must they be exchanging?
Perfect
must I have exchanged? must you have exchanged? must he have exchanged? must we have exchanged? must you have exchanged? must they have exchanged?
V-ing perfect
must I have been exchanging? must you have been exchanging? must he have been exchanging? must we have been exchanging? must you have been exchanging? must they have been exchanging?
Interro-negative form
Simple form
must I not exchange? must you not exchange? must he not exchange? must we not exchange? must you not exchange? must they not exchange?
V-ing form
must I not be exchanging? must you not be exchanging? must he not be exchanging? must we not be exchanging? must you not be exchanging? must they not be exchanging?
Perfect
must I not have exchanged? must you not have exchanged? must he not have exchanged? must we not have exchanged? must you not have exchanged? must they not have exchanged?
V-ing perfect
must I not have been exchanging? must you not have been exchanging? must he not have been exchanging? must we not have been exchanging? must you not have been exchanging? must they not have been exchanging?